document.write( "Question 1151261: An urn contains 6 green and 7 red marbles. Five marbles are selected. In how many ways can this be done where at least one marble is red? \n" ); document.write( "

Algebra.Com's Answer #772956 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "From the context, the marbles differ by their colors only (since the opposite is not stated).\r\n" );
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document.write( "Let R be the number of red marbles among 5 selected marbles.\r\n" );
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document.write( "Then the number of different cases (the number \"in how many ways can this be done\") is equal to the number of solution to this inequality\r\n" );
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document.write( "    1 <= R <= 5.\r\n" );
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document.write( "The number of solution is 5.\r\n" );
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document.write( "Therefore, the ANSWER to the problem's question is 5.\r\n" );
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